Can-testing machine



1,694,132 C. D. MGDCNLD CAN TESTING uAcHINE Filed June 6, 1927 7 ,SheeisQSheet' 1 I 77/527 gf/) Decn l4, 192s.

1,694,132 C. D. McDONALD GAN TESTING uAcHINE Filed June 6, 1927 7 Sheets-Sheet 2 D@n 4, 192s. 1,694,132

` l C. D. MCDONALD CAN TESTING MACHINE Filed June 6, 1927 7 Sheets-Sheet 4 5U/@lato 7"/ A7.90 i y C. D. McDONALD GAN TESTING MACHINE Filed June 6, 1.927

7 Sheets-Sheet y5 Dec. 1928.,

C. D. MCDONALD CAN TESTING MACHINE 7 Sheets-Sheet 6 Filed June 6, 1927 www Patented Dec. 4, 1928.

uNlTED s TATVEs IPATENT OFFI QHAnLEs D. IIGDONALD, OF cm'caeo, ILLINOIS, .AssIoNon To MCDONALD- MAGIIINE oo., OF CHICAGO, ILLINOIS, A CORPORATION or ILLINOIS.

` CAN-TESTI'NG MACHINE.

application 111e@ June e, ma' serial No. 196,935.

This invention relates to can testing machines, land its principal object is to provide a pneumatic or compressed air can'testing machine of novel construction, capable of operating upona maximum number of cans in a minimum amount of time and occupying a comparatively small floor space, and ca; pable of o erating with great certainty, delicacy an accuracy in automatically testing or separating imperfect or leaky cansv from hermetically tight or perfect ones. Another object is to provide improved means for automatically admitting compressed) air to the cans after they have been delivered to the machine and thereafter sealing the cans, against the escape of the compressed air while the cans are being carried to the selecting .11;1echanism,A and thereafter cstablishing communication between the interi-or of theV cans and a pneumatically operated selector which controls mechanism for separating the imperfect or leaky cans from the hermetically tight or perfect ones.

With these and othervobjects and advantages in view, 'this 4invention consists in a can testing-machine embodying a movable carrier equippedwith a plurality of compressed air balancing tanks, one for each can orpair of cans, and associated sealing heads and can clamps for clamplng the cans against the heads, in combination with compressed air conduits and valve mechanism for admitting compressed air to the cans and associated vcompressed air balancing tanks operated selector or a'pair .of selectors at the discharge end of the machine which are operated by an unbalanced pressure in any compressed air balancing tank and an associated can which is clamped on its associated' and trapping the air therein at the receiving'` end of the machine, and a pneumatically The invention is clearly illustrated in the 2 is a vertical cross section takenon the line 2-2 of Fig. 1.; Fig. 3 is a detail section taken on the line 3 3 of Figs. 1 and 4 and showing two cans secured in place on one of the can holding heads of the machine; Fig. 4 is a fragmental View in side'elevation of the parts seen in Fig. 3, with certain portions broken out to illustrate parts that' would otherwise be' hidden from view; Fig. 5 is a detail side elevation of the can separating mechanism; Fig. 6 is a plan of the parts seen in Fig. 5; Fig. 7 is an enlarged side elevation of one of the selectors which forms part of the present invention, the glass cover thereof, being removed; Fig. 8 is a-vdetail vertical cross section taken on the line 8-f-8 of Fig. 7 ;v Fig. 9 is la rear elevation of the selector seen in Figs. 7 and 8 with its supporting plate removed ;"Fi 10 is a detail cross section of the selector ta en on the line 10--10 of Fig. 9; Fig. 11 is adetail plan of a certain link connection which forms part of the selector mechanism; Fig. A12 is a detail cross section taken'on the line 12-12 of v9; Fig. 13 is a detail vertical cross section of an air valve device, the line of section being indicated at 13-13 of Fig. 2; Fig. 14 is a detail horizontalsection taken on lin' 14-14 of Fig. 18; Fi 1-5 isla detail view, partly in plan'and part y in section, of the selectors 1;

and certain air controlling means, the'line of section being indicated at 15 15 in Fig.

1; Fig. 16 is a detail front elevation of a certain track or guide'way for operating the canclamp s;' Fig. 17 is a side elevation of the parts seen in Fig. 16; Fig. 18 is a detailview, partly in side elevation and partly in vertical section of certain valve actuating mechanism for the air valve device, the line of section being indicated at 18-18 of Fig.

1, and Fig. 19 is an elevation of the clamping mechanism of one of the can clamping heads.

Referring to said drawings,wh1ch illustrate a simple embodiment of the invention,

and first to Figs. 1 and 2, a base 20 is provided, upon which is mounted thc body or standard 21 of the machine, the upper end of which is formed with bearing boxes 22 in which is rotatively mounted the carrier head 26 that carries the cans through the machine. The carrier head has a hub 26 and a hollow shaft 23 which are journaled in said bearing boxes, and the head is rotated by any suitable mechanical means, as for .instance a worm gear 24 mounted on the hollow shaft 23 and meshing with a Worm pinion 25, driven from any suitable source of power.

As illustrated, the carrier head is provid- Ved with a multiplicity of circumferentially arranged can clampin heads 27 and each can clamping head is ormed with two can clamping members (see Fig. 3) whereby t-wo cans may be carried by the same head.

'Each head is formed with a clamping plate 0r abutment member 28 against which the two cans are clamped, one on each side thereof, and a pad 29 is secured upon one side of the plate- 28 for enga ement with the open end of one can. Tie clamping plate 28 projects from a boss 30 formed as a separate part of, or as an integral part of' the carrier head 26. Slidably mounted on a spindle 31, secured in the boss 30, are clamping arms 32, 33, on which are secured Acan clamping discs 34;' 35, which discs are preferably provided with stems 36, 37, ad- ]ustably'secured in the arms 32, 33 for the purpose of adjustment Vfor long and short cans. The disc 34 may be made solid for engagement with the closed end of a can, whereas the disc '35 is provided with a resilient clamping pad 29a for engagement with the open end of the can and making a tight fit thereon, and the stem 37 is made hollow and opens out through the outer face of the pad 29, whereby compressed air may be supplied to the interior of the can clamped thereon and from said openi'n'g leads a conduit which runs to an air valve as will be described hereinafter. Links 38, 39 are connected to the disc supporting arms 32, 33 and the free ends of said links are connected to a lever 40 which isr provided with an ,arm 41 on which is mounted a roller 42 that engages with a track or grooved guide way 43, (see Figs. 16, 17) mounted on some stationary portion ofthe machine as for instance the base 20. A can carrier 28n (see Figs. 3 and 4) is secured to each can clamping head and has a concave seatfor receiving the can as it is delivered Ito the can clamping head from the dellvery chute, and said can carrier operates to locate the can in position to be clamped in place by the clamping mechanis-m. The track 43 is located in position to engage with the rollers 42 at the place where the can clamps discharge the cansfrom the have been delivered to the can clamps whereby the cans are clamped in place 'as they start their passa e througlrthe machine. A feed chute 4 is provided at the receivin end of 4the machine, through which t e cans, to be tested, are delivered to the can clamping heads. It will be understood that directly after each can is clamped by -a "can clamping head, compressed air is admitted to the can and to an associated balancing tank, one for each can or associated pair of cans, and the air is thereupon trapped 'inf said cans and balancing tank and held therein while the cans are carried around by the carrier to the discharge end ofthe machine, where communication is established between the cans, their associated tank and the testing4 apparatus. where the hermetically tight cans are selected and separated from the leaky cansa of compressed air balancing tanks 50 will ben seen mounted on the carrier` 26, there being one tank for each can clamping head. Compressed air is admitted simultaneously to a tank 50 and to the can or cans clamped to the associated can clamping head, said compressed air being supplied from a compressed air reservoir 51, here shown as contained in the body 21 of the machine and supplied with compressed air by any suitable air compressor. A compressed air pipe 52 leads from said compressed air reservoir' 5l and delivers compressed air into a stationary tubular member 53 contained within the hollow of the shaft 23 and hub 26a, and extending from the rear end thereof to the front of the mechanism as is clearly seen in Fig. 2. Into the other end of the tubular member '53 is screwed a fitting 54, from whicl `leads a compressed air pipe 55 that discharges into the air chamber of, an air valve device 56 (see Figs. 13, 14) from which lead three compressed air pipes 57, 58,59 that run to ports or perforations in a'shoe 60 supported in a stationary disc like head main air chamber of the airvalve device 56 and the several compressed air pipes 57, 58, V59 which lead therefrom, are valves 62, 63, 64 (see Fig. 13) whichare normally closed, but which are arranged to be opened by the action of the cans themselves, directly after they` have been clamped in place by the can clamping heads. As shown the valve actuating mechanism for the valves 62, 63, 64, comprises arms 65, 65a (see also Fi 18) one for each of the pair the carrier, which arms are mounted on rock shafts 65", 65, on which are other arms 66, 66a which are connected to links 67, 67"l 'that are connected to the valve actuating levers 68, 68a by bell crank levers 69, 69, links 70, 7 Oa, the bell crank levers 71, 71a and links 72, 72a. The valve actuating levers 68, 68l are mounted upon the casing or frame-of the ai'r valve device 56 and have'arms that are arranged to engage with the stems of the valves 62, 63, 64 to unseat said 4valves whenever the valve actuating levers 68, 68a are is arranged to-unseat the middle valve (as seen in Fig. 13) and the endxvalve 62 or 64, associated with the lever. Each end valve 62 or 64 controls the compressed air conduit for one mitted to the air conduit leads.`

.tanks have been filled vbecomes necessary ca n of each pair 'of cans, and when one of said valves 1s opened, compressed air is adcan to which the compressed head passes the valve actuating levers 65, 65a with only one can clamped in place, only one lever 65 or 65a will be actuated and consey quently only one end valve 62 or 64 will be opened. The middle valve 63, however, -will be opened,whenever either end valve 62 or 64 is opened, whereby compressed air will be admittd to the can held by the can clampi g head and to the balancing tank 50 associat/iid with said head.

After the cans and associated balancing with compressed air it to trap the air in the' cans and tanks while the cans are being carried around to thedischarge end of the machine. T he mechanism for pressed air, delivered from the valve device 56 to the cans and associated balancing tanks will now be described.

The compressed air pipes 57, 58, 59 lead to the shoe 60 as above described and said shoe bears against a ring 73 mounted on the carrier 26 and secured to it by an annular bracket 74 (see Figs. 2 and 3). In said ring 73 are formed ports 75, arranged in concentric rows in the` ring 73 and arranged to be brought into register with the ports for the air pipes 57, 58, 59 that terminate in the shoe 60. Leading from said ports4 7 5 are air pipes 57, 58a, 59, one set for each balancing tank 50 and associated clamping head. The air pipes 57a, 58, 59,- form extensions 'to the compressed air pipes 57, 58, 59 and lead to of cans, carried by 'through the associated In case`a can clamping 77 controlling the comcasing ciated air pipes 57a, 57h, 5 8", 58b and 59, 59", y

whereby when the valve 1s' opened, the compressed airv may pass through the valve from one set of air thence to the cans and balancing tankassocated therewith. Each ipe extension 57b leads to and through a pa r extension 59h leads to and through a pad 29, while each pipe extension 58b leads to the air balancing tank 50 associated with said pads. On the end of each valve stem 76 of the air 77, which is arranged to engage with a roller 78 mounted on a bracket 79, which is carried by the stationary head 61. The arrangement is such that as the valves 150 move past the roller 78, the valve actuating arm 77 of each valve encounters the roller and is thereby partially rotated so as to close the passages valve 150 thereby trapping the compressed air in the associated cans and balancing tank. At the discharge end of the machine is a roller 80 mounted upon abracket 81, also secured to the stationary head 61 and said roller 80' is larranged to engage the valve actuating arms and turn said arms back as they pass by said roller, thereby again opening t e passages through the associated valve 150 and permitting the compressed air to escape fr om the associated cans and balancing tank -to the selectors. The valves 150 remain open after the cans have been charged from the carrier again closed after other cans have been delivered to the samecan clamping head as the 29, and each pipe valves 150, is a valve actuating arm.

tested and disf heads, and are pipes to the 'other set and les one from which selected cans have been disl charged.

The selectors, designated by the reference letters A, A1, are mounted `upon the s tatlonary head 61 ofthe machine (see Fig. 15) and contain pneum'atically operated mechanism which is arranged to `be placed l1n communication with the cans and associated balancing tanks just prior to the time that the cans are released .from the can clam lng heads and discharged from lthe mac me. The selectors are similar inconstruction and a description of one of them will suiiice for both. f

Referring now to Figs. 7 to 12, inclusive, as shown, each selector is provided with a 82, having a supporting plate 82a which is ,bolted or otherwise secured to the stationary head 61 of the machine and va glass door or cover 82". .Mounted in the hollow of' said casing are twoi'bowed, tubular air gauge `springs or tubes l83, 84 formed at their free ends, and secured to and openlll) .gauge tube communicates with a balancing i same can clamping heads.

`the pressure in both the twotubes expand or straighten out tank 50 during the interval in which a port of the middle row of ports in the ring 73, passes the middle port of the shoe 87.- The air gauge tube 84 and nipple 86 of one selector connects with a port in the shoe 87 through an air pipe 89 and the air gauge tubey 84 and nipple 86 of the other selector connects with another port 1n the shoe 87 by an air pipe 90. The port in the shoe 87. for the air pipe 89 of selector A, is arranged to come into register with the ports of the air pipes 57 l that run to the valves 150 and froml which lead the pipes 57" that run to the pads 29 of the can clamping heads (see Fig. 3) andthe port for the air pipe 90 of selector A1, is arran ed to come into register with the port o -the air pipes 59a that run to the valves 150, from which lead the pipes 59b that run to the' pads 29a of the The arrangement of the ports and air pipes is such that whenever any three aligned orts in the ring 73 come into register with t e three orts in the shoe 87, communicationl is esta lished between a balancing tank 50 and the air gauge tubes 84 of the selectors, the air conduit for one can being o ened to the tube 84 .of the selector A, and t e conduit for the other can being opened to the tube 84 of theother selector A1. When compressed air is admitted to the companion air gau e tubes 83, 84, theytend to expand or straighten out under the influence of the compressed air, and if air gauge tubes is equal the same degree. However, if the pressure has fallen in one of the cans, the air gauge tube communicating therewith will expand or straighten out less than its companion air gauge tube, whereby mechanism is set in motion which causes the leaky cans to be discharged from the machine into a different place than the hermetically tight ones.

Rotatively mounted in a bearing bracket 91 contained in the casing 82 is an arbor 92 which is preferably provided with ball bearing or other anti-friction bearingsiwhereby equally or to y the arbor may rotate freely, and secured upon one end of-said arbor is a crank arm 93, one end of which is connected to the closed ends of lboth air gauge tubes 83, 84'

by links 95, which are preferably made adjustable lengthwise of each other to afford a close adjustment between .the crank arm 93 and the closed endsof the air gau e tubes 83, 84. Secured upon the other end of the arbor 92 is an arm 96 which is preferably counterbalanced 'at its upper end and mov-V able between two stop pins 97 which are secured in the front wall 98 of the casing 82. Normally the arm 96 stands in a neutral position as indicated in Figs. 7 and 8, but whenever the arbor 92 is turned upon 'the axis (which occurs when there is an unequal expansion or straightening, out of the companion air auge tubes 83, 84) then the arm 96 is move out of its neutral position and becomes effective for the purpose of separating out a defective can.

In the form of the invention illustrated, the lower end of the arm 96 is provided with an enlargement of thickened portion 99, which is i terposed between-two reciprocable motion transferring members 100, 101

which are slidably mounted in the body ofl the casing 82., A notch 102 is formed in they member 100 which notch is in alignment with the arm 96 and its enlargement 99 whereby said member 100 may be reciprocated independently of the member 101 so long as the arm 96 remains in alignment lwith the notch 102. iIn case-the arm 96 is moved out of alignment with the notch it becomes interposed between the solid portions of said members 100, 101 whereby i whenever the member 'is moved in a direction toward the arm 96, the member 101 will be correspondingly moved because of the interposed part of the arm' 96, and said endwise movement of said member 101 is used for transmitting motion so as to defiect a certain track or run way for Athe discharge of the cans, whereby a defective can is discharged through a different discharge track or. run way than the perfect can. 1n the form of motion transmitting members 110, 101 shown, the member 100 has a late 103 on its forward end which contains t e Ynotch 102 and the member 101 has a plate 104 secured to its adjacent end, which lies behind the plate 103.- Coiled com ression springs 105 contained between shoulders on the members 100, 101 and the bottoms of recesses formed in the body of the case 82, serve to yieldingly hold the members 100, 101 in the position shown in Fig. 8 of the drawing.

Journaled in suitable bearings mounted on the frame work of the machine is a .cam shaft 106 (see Figs. 1 and 5) which is driven to make one complete revolution for the purpose of selecting the cans of each can clamping head, and on one end of said cam shaft 106 is a cam block 107 which contains a cam that is arranged to engage with a roller 108 once during each revolution in turn move th i* as which form sto'ps 124 surrounding tion transmitting member 100. The a'r-I rangement of the parts is such that .whenever the cam of the cam block 107 swings back the lever 109, it draws down the link 110, swin s both levers 111 and 112, thereby rocking th therewith the crank arms 114 thereof, which e member in theJ direction of the arrow thereon in Fig. 8. If the can or cans are sound, which are in communication with the selectorsv at .the time the member 100l is moved, the arm 96 remains in neutral position thereby permittin the notched plate 103 to pass the arm96 an without affecting the member 101. If, however, the pressure'ineither or both of said cans has beomelowered and the arm 96 of the selector for said unsound can is to be swung out yof .y its neutral position, the notched plate 103 engages the' enlargement of the arm 96 and through it moves the member 101 in the directionu of the arrow thereon in Fig. 8, whichhas the effect of setting into action certain can separating mechanism as will be presently described. For the purpose of adjustably locating the normal stationary position of the motion transmitting members 100,' 101, with respect to the arm 96, adjustment screws 145, 146, are provided against which the crank arms strike when the members 100, 101,

reach theirproper normal stationary position t with the arm 96 between them.

Journaled casing 82 opposite the rock rock shaft 117 which yupon its inner forked part 119 vin a boss upon the side of each shaft .113, is a has a crank arm 118 end that engages with "a of the member 101. Upon connected to a link 121 that runs to a crank arm 122; It will be understood that the crank arm 120 of each selector is connected to a separate link 121vand that each link 121 is connected to a separate arm 122. One of the arms 122 is mountedl upon a rock shaft 123 (see Figs. 5 and 6) jourrfaled in the frame work of the machine and the other arm 122 is mounted upon a sleeve said shaft 123. vSecured i vupon the sleeve 124 is a detent setting member 125, and secured upon therock shaft 123 is a similar detent setting member 126, each of which members are held in retracted positions by a coiled tension spring 127 as-seen in Fig-5. y Rotatively mounted on stud shafts 128 seerwise secured.

e shafts 113 of each selector and discharge chute 135 136, .one track way for eachrow of cans con- 9o said rock shaft 117 is anl f from which they are discharged. into of the machine and cured in the framework of the machine are two A trap door operating levers 129, 130. Said levers 129, 1,30 are arranged to bei actuatedby cam blocks 131 rigidl'ymounted on the shaft 106. the same stud shafts 128A are levers 132, which are provided with 133 that are adapted to engage in notches y 134,Y formed in the levers 129, 130, whenever the associated detent setting arm is actu- 75 ated. Thearrangement is such that the cams 131 may rotate and oscillate the trap door actuating levers 129, without affecting the levers 132, vbut whenever the detent 133 of either notch 134 then the two levers 129 or 130 and '132 become v'rigidly connected together 'so v thatthe movement imparted to the lever 129 or 130 by a cam block 131 is transmitted to an associated lever said lever is'depressed, thereby swinging up a trap doory for discharging a defectlve can. At the'discharge end of the machines is a in which are track ways tained on the carrler/ The forward ortions 136a of said track ways are mova le and form trap doors that are mounted upon rock shafts 137, '137% and said rock shafts 137, 137'i have arms 138,4 13,8*11 secured thereto, whichl 95 I arms are connected to the levers 132g by links 139. Coiled tension springs 139a connect the levers 132 with some stationary portion of theJ frame work and act to swing said levers upward and therewith hold the trap 'doors' 100 136a in the position indicated in Fig. 5 wherei in the solid or perfect cans may rolldown when discharged from the carrier head and be delivered in a suitable receptacle or.other wise disposed of. Below the tracks 136, 136 155 are other tracks 136b upon which the imper fectcans are discharged, it being understood that when an imper ect can or cans reach a position where it would otherwise be disl charged upon the trap door or doors 136a 11o that such -track portfon's are swun upward by the track door actuating means described,

ar enough to permit the imperfect can or cans to fall upon the lower track ways 136",

other receptacle, rack., orreceiver.

Can ejectors 140 (see Fig. 1) may-be employed atthe discharge end of the..=machine for ejecting the testedI cans from the can clamps. of L shaped arms, the bent ends of which l'e'in the paths of movement of the cans," and said ejectors are fulcrumed upon the-frame connected to a lever 141 by a link 142 (see Fig. 5). on the shaft 106, and substantially like the cam 107, is arranged to engage a roller onl said lever 141 in timedrelation to the in stant of discharge of the cans, and swings down'J said lever 141, thereby drawing-down 13G Rotatively mounted on 7o spring actuated detents lever 129, 130 is swung into the 80A 132 and the far end of 85 Some 115 `Said can ejector-s are in' the form v120- A cam block 143 125 on the link 142 and swinging down the ejectors upon the cans and ejecting them from the carrier.

In the operation of the machine, the carrier is rotated in the direction of the arrow7 in Fig'. l1 and compressed air is supplied to the compressed air chamber of they an' valve the pads 29, 29 of t both cans and associated tank is there' .of operations except that if a can the arm 65 for that device 56. When the construction shown is used, compressed voir 51and piped to the air valve device 56 as heretofore described. The cans to be tested are laced in the chute 47 with the open ends t ereof in osition to engage with e can clamping heads. The cans roll down thechute and enter the can carriers and directly roller 42 of the can clamping mechanism rides up the inclined part 46 of the track or guide way 43 and draws the links 38, 39 past an imaginary line extending through the pivot points -of the links and pivot point of the lever 40 thereby locking the links in clamping position. The clamping discs connected to said links thereby clamp the cans againstthe pads 29,129. As the cans pro- `ceedlthey encounter the valve actuating arms the valves 62, 63, 64 of the air valve device 56. The air valve 150 has been opened before this time and at the` time the valves 62, 63, 64 are opened, the ports 75 of the air pipes 57 58, 59, in the ring 7 3 register wlth the ports in the shoe 60 for the air pi es 57, 58, 59, ,and compressed air flows t rough the air pipes 57, 58, 59, shoes 60, 73, air pipes 57, 58, 59, valve 150, through pipes 57", 59b and into the cans, and through pipe 58b and into the associated air balancing tank 50. Immediately thereafter the arm 77 of the air valve 150 encounters the roller 78, which turns the arm and therewith closes the valve 150, thereby trapping the compressed air in the two cans and associated Vtank 50. The pressure in and open the start.y The same sequence take place with other cans that are delivered to the can clamping heads, fails to enter any head side of the carrier is' not actuated by a can and consequently the end valve 62 or 64 for the empty part of the can clamping head remains closed. f

The carrier carries the cans around to the discharge end of the machine, which is close to the receiving end and as the ports for the air pipes 57, 58, 59n begin to register with the ports in the shoe 87 for the air pipes 88, 89, 90 that lead to the air gauge tubes 83, 84 of the two selectors A, A1, tli-e arm 77 of the air valve 150 engages the roller 80 and is turned back, thereby opening the valve 150 and permitting the air under pres sure from the two cans and associated tank 50 to enter the air gauge tubes` 83, 84, causing them to expand or straighten out. It' at fore equal at air is supplied to the reser` thereafter thearm 96 will be left in neutral position,

however, the pressure in either can is lowered, due to a leaky can or otherwise, the air gauge tubes will expand unequally, the crank arm 93 will be partially rotated, and the arm 96 turned slightly', thereby bringing its end out of alignment with the notch in the member 100 and interposing said end between the solid parts of said members 100, 101. l

At the instant the arm is so interposed between the solid parts of the members 100, 101, the cam on the cam block 107 encounters the lever 109, swings it down, theres by drawing the link 110 down and moving motion transmitting members 100 toward the members 101, through the instrumentality of the link 110, levers 112, rock shafts 113, and crank arms 114. In the 84, will expand equally and the I selector or selectors where the arm 96 remains neutral, the member 100 is moved idly, but in case pressure in one of the cans has lowered, the arm is swung over between the solid parts of the members 100, 101, and the member 101 is thereby moved endwise by the member 100. Motion is thereby transmitted from the member, 101 to the arm 122 (see Fig. 5) by the crank arm 118, rock shaft 117, lever 120, and link 121, and the sleeve or rock shaft 123 or 124 connected to such arm 122 is turned thereby, forcingthe detent setting arm 125 133, and moving said detent into the notch of the lever 129 or 130 as the case may be, at which time the cam or the cam block 131 encounters the lever 129 or 130, moves it upward, thereby moving down the lever 132, and moving upward the' trap door 136 through the instrumentality of the link 139, arm 138, or 138a door is secured. The imperfect can therefore drops upon the track way 136b and is discharged through one pas*- sage, and the sound can falls upon theun raised trap door and is discharged through another passage. As the cans arrive at the discharge place, the ejectors 140 engage the cans Vand eject them from the can carrier. It'will be observed that after the cans have beentested by the selectors, of thecan clamping head encounter the inclined part 44 of the guide way 43 and move back the can clamping discs, thereby releasing the cans, whereby they are free to discharge from the carrier.

From the above it will be seen that compressed air is admitted to each balancing tank and the cans associated therewith, at the receiving end of the machine, held in the tank and-cans for a predetcrlni ned length of time, to permit air to escape Jfrom a leaky can and thereby lower the pressure therein,

against the detent the rollers 42 Y lob ' and thereafter the air from each tank and cumferential row of cans in order to test the cans of the separate rows the tight cans fromthe leaky ones.

It will be understood that the selector or selectors must be adjusted carefully to oper- `ate withcans of a given capacity andythat when cans of a dill'erent capacity are to be tested theselectors must be adjusted corres ondingly. Furthermore, because of the d1 erence in length of the air conduits leading from the balancing tanks to the selectors and those leading from the cans to the selectors, the Selectors must be,Y adjusted to compensate fo'r any slight diierence in pressure produced-"in the opposed air gau springs when-the air is exhausted from t e balancin tanks and cans into the selectors. While t e pressure which is put into the tanks and cans may be equal, when returned to the selector, the. ressure in one air gauge s ringwmay be `slig tly lower than that 1n t e ot r air gauge spring, and must be compensated for so that the arm 96, which isv interposed between lthe Fmoving element 100 and the element 101 `moved thereby, may stand behind the notch 102 to render the element 101 inactive if the can being tested is light, despite Athe fact that the pressure in Iprecisely justably the two air gauge springs is not equal. The arm 96 is therefore a secured upon the arbor92 as for instance bv a clamp'member 96x (see Figs. 7--and 8) and .clamp screws 96?. The adjustment is made by using a known tight can and when the air gauge springs are extended from the pressure received from a balancingv tank and the tight can, adjustin the arm 96 to stand in a neutral position ehind the notch 102, and tightening up the clamp to llock the arm 96 on the arbor 92. Obv1ously the arm may be out of register 'with the 'notch when the air gauge springs are relaxed,'b`1'1t whenever the air ressure from the tanks and associated tig t cans is exhausted into the air gauge sprin s, the arm is moved into neutral position' ehind the notch.

While the machine has been shown and described with can clamping heads and pads for holding two cans in each head, the heads may be made to hold one or more cans, and

the number of selectors made to correspond with the number of cans carried by any one head. l With this construction shown only one selector is required for each circumfer" ential row of cans idiereby greatly simplify ing the construction and cost of the machine. l

and separate .out

While the selectors are shown and described as employing opposing air gauge springs for actuating the arm 96, other vequivalent pneumatically operated mecha- -nism may be substituted wherein opposed pressures areemployed for moving the pneumatically operated device.v 'i

It will be observed that although the pressure in the supply reservoir may vary considerably durin a days run, the selectors will operate with equal delicacy and certainty regardless of such variation in pressure. Moreover, the mechanismis entirely automatic in operation and requires only the usual attention given to mechanical opposi- ,tions of like character.

More or less variation of the exact details of construction'is ossible without departing from the spirit ci) this invention; I desire, therefore, not to limit myself to the exact form of the "construction shown and .described, but\intend, inthe following claims,

to point out all of the invention disclosed herein.

"I claim as new, and desireto secure by balanced air gaugesprings arranged to be connected respectively to a can to be tested.

and to an associated air balancing tank, motion transmitting means for transmitting motion from a prime mover to a can separating mechanism, and normally inactive means, operated by said air gauge springs under the influence of differential pressure therein, and forming an operative connection in said motion transmitting means.

` 2. In a cantesting machine, a pneumatically operated selector comprising a pair of balanced vai;` gauge springs, adaptedl to be connected respectively with a can to be tested and an associated air balancing tank, a primary, motion transmitting element and an associated, normally inactive, motion transmitting element for transmitting motion 4to a can separating mechanism, an inter osed member between said motion transmitting,

tion whereby motion is transmitted from.

said primary power transmitting element to said normallyinactive motion transmitting element. Y

3. In a can testing machine, a selector comprising a pair of oppositely disposed air gauge sprlngs stationarily mounted at one end, and, 'said' end of one spring being' adapted to communicate. with acan to be` tested and said end of the other spring being adapted to communicate with an associated air balancing tank, a continuously operating motion transmitting element and a normallyinactive motion transmitting element for transmitting motion to a can selecting mechanism, an interposed member between said motion transmitting elements, normally occupying an inactive position, and operative connections between the free ends of said bowed air gauge springs and 'said interposed member.

4. In a can testing machine, a selector comprising a pair of bowed air gauge springs, one end of both of Whicliis stationarily supported, one spring being adapted to communicate with a can to be tested and the other adapted to communicate with an assoiated air balancing tank, an arbor, a

Y cranktliereon, links connecting the free end of said air gauge springs with said crank, a continuously operatingmotion transmitting element and a normally inactive motion transmitting element, for transmitting motion to a can separating mechanism, and an interposed member mounted on said arbor and normally occupying an inactive position between said motion transmitting elements, but movable into an active position under the influence of differential pressure in said air gauge springs.

5c In a can .testing machine7 the combination of a pneumatically operated selector having a pair of bowed air gauge springs,

one adapted to communicate with aA can to be tested and the other adapted to communicate with an associated air balancing tank, motion transmitting elements, and an interposedmember operated b' said air gauge springs and movable un er the influence of a differential pressure in said air gauge springs, from an inactive to an active position between said motion transmitting e e-v ments, means for actuating one of said motion transmitting elements, and trap doorcan-discharge mechanism capable of being operated by the other motion transmitting element.

6. In a can testing machine, a pneumatically operated selector comprising a pair of balanced air gauge springs arranged to be connected respectively to a can to be tested and to an associated air balancing tank, a reciprocatory motion transmitting element, a normally4 inactive motion transmitting element, one of said elements having a notch therein, and an interposed member between said motion transmitting elements, normally located in line with said notch, and operative connections betweenl said air gauge springs and interposedmember; q

7. In .a.. can testing machine, a selector comprising a pair of bowed lair gauge springs, one end of both of which is stationarily supported, one spring being adapted to communicate with a can to be tested and the other adapted to communicate with an associated air balancing tank, an arbor, a. crank thereon, links connecting the free end of said sition in line with said notch, and mova le into an active position under the influence of differential pressure in said air gauge springs.

. In a can testing machine, the combination of a carrier having a multiplicity of can sealing pads and associated can clamping heads thereon, balancing tanks, one for each head, nicunted on said carrier, means for admitting fluid, under pressure, to a can held by a can clamping head and to an associated balancing tank, means for trapping said fluid in said can and tank, can selecting and separating mechanism including a pneumatically operated selector, and means for establishing communication simultaneously between said can and selector and said balancing tank and selector.

9. In a can testing machine7 the combination of a carrier, ,having a multiplicity of can sealing pads and associa-ted can clamping heads mounted thereon, balancing tanks, one for each head, mounted on said carrier, means for admitting compressed air to a can held b a can clamping head and to an associated alancing tank, including air control means actuated by the cans, means for -trapping compressed air in said can and balancing tank, can selecting and separating mechanism, including a pneumatically operated selector, and means for establishing communication between said can and selector, and said tank and selector.

10. In a can testing machine, the combination of a carrier having a multipl"` city of can sealing pads and associated Vcan clamping heads mounted thereon, air balancing tanks, one for each head, mounted on said carrier, means for admitting compressed air to a can held by a can clamping head and to an associated air balancing tank, means for tra ping said compressed air in said can and tan a selector having two bowed gauge springs, normally inoperative motion transmitting means, and an interposed element operated by the bowed gauge springs; means for admitting air from a can to one of said bowed gauge springs and from an associated tank to the other bowed gauge spring, and can separating mechanism controlled by a member of said motion transmitting means.

11. In a can testing machine, the combination of a rotatory carrier having a multiplicity of can sealing pads and associated means for trapping compressed airin said can and associated air balancing tank, can

selecting and' separating mechanism includ-y ing a pneumatically operated selector, and means for establishing communication between said can and selector and said air b alancing tank and selector-L 12. In a can testing machine the combination of a rotatory carrier having a multiplicityof can sealing padsand associated can clampingheads arranged circumferentially about said carrier andmounted thereon, air balancing tanks, one associated with each can clamping head and mounted on said carrier, 'a source of compressed air supply, individual compressed air conduits for said cans and associated air balancing tanks arranged to communicate with said source of compressed air supply, air valve devices interposed in said conduits, means arranged to close said valve devices and thereby trap compressed air insaid cans and associatedair balancing tanks, can selectingr and separating mechanism, including a selector hav- `when the said individual compressed air coning two balanced air gauge springs and inotion transmitting means controlled thereby,

air conduits leading from said air gauge springs, and arranged to communicate with said individual compressed air conduits, and means for opening said air valve devices,

duits are communication with said air gauge spring conduits.

13. In a can testing machine, the combination of a rotatory carrier havin mounted thereon .'a 4multiplicity' of circum erentially arranged can sealing pads and associated can clamping heads, air'balan'cing tanks, one for each can clamping head, a source of coinpressed air supply, compressed. air Vconduits for simultaneously conducting compressed air to cans held by said can clamping heads and associated air balancing tanks, air valves interposed in said conduits, means for closing said valves at the receiving end of the machine and for opening said valves at the discharge end of the machine, can selecting and separating mechanism, including a pneumatically operated selector, operable under a differential pressure in a can and associated air balancing tank, to separate leaky cans from tight ones, and conduits for establishin communication between said compressed Y.air conduits of the cans and air balancing tanks and selector while said valves are open.

14. In a can ltesting' machine, the combination of a rotatoxy carrier having circumferentially arranged can sealing pads and can clamping heads thereon, air balancing tanks, one for each can clamping head vmounted on said carrier, a source of' compressed air supply and compresed an' conduits leading from said source of compressed air supply, one conduit being for thecans to be tested and one for the balancing tanks,

valves controlling said conduits, a lever lying inthe path of movement of the cans and actuated by said cansand operative connections between said lever and valves for opening said valves and thereby permitting compressed air to pass to the cans, a'stationaril mounted selector, and'means forl establis ing communication simultaneously `between said selector and a moving can and associated air balancing tank.

15. In a can testing machine, the combination of a-rotary can carrier having circumferentially yarranged can sealing pads and can clamping heads mounted thereon, air balancing tanks, one associated with each can clampingv head, means for supplying compressed air simultaneously to a can clamped in said clamping head and to an associated air balancing tank, a stationarily mounted selector, and means orestablishing communication simultaneously between said selector and a moving can and associated air balancing tank, said selector includinga primary motion trnsmitting element and a normally inactive'motion transmitting element actuated thereby.

16. In a can testing machine, the combi` nation of a continuously rotating cam shaft, cams. mounted thereon, a lever actuated by one of said cams and a trap door actuating lever actuated by another of said cams, a pneumatically. operated selector having motion transmitting elements, each connected'to one of said levers, the trap door actuating lever having a normally inactive arm' connected. to the trap door, and setting mechanism actuated by the first mentioned lever for' setting said trap door actuatinglever into operative position.

17. In a can testing machine, a selector, a primary motion transmitting element and a normally inactive motion transmitting element, a pair of air gauge springs adapted to communicate with acan to be tested and an associated air balancing tank, means operated by said air gauge springs for operatively 'connecting' said elements, -a rock shaft 'and means for rocking said rock shaft, a crank arm on said rockshaft engaging with said. primary motion transmit-y 1'25 ting element, a crank 'arm engaging with said normally inactive motion transmitting element, a rock shaft on which said last mentioned crank arm is mounted and can separating mechanism operatively connectedto said last mentioned `rock shaft. l

'idly except when said arm is moved out of normal position, a continuously rotating shaft and operative connections between said shaftand primary motion transmitting element for continuously reciprocating said element, a trap door for separating leaky cans from tight ones and operative connection between said trap door and said secon'd mentioned motion transmitting element.

19. In a can testing machine the combination of a carrier having a multiplicity of can sealing pads and associated duplex can clamping heads thereon for clamping-two rows of cans in the heads, air balancing tanks, one for each twoI cans held in each head, means for admitting compressed air to each can held by said heads and simultaneously to an associated air balancing tank, means for trapping compressed air in said cans and associated tanks, can selecting and separating mechanism for each row of cans, including a pneumatically operated selector for each row of cans, and means for separately establishing communication between the cans of one row and their associated air balancing tanks with one selector, and between the cans of the other row and their associated air balancing tanks and the other selector.

20. In a can testing machine, a can clamping head having a stationary clamping membei', a can sealing pad thereon, oppositely disposed, can clamping discs arranged to clamp two cans upon said stationary clamping member, one of said discs having a can sealing pad thereon, clamping arms supporting said discs, and arm actuating means for operating said discs, there being compressed air conduits leading from-said can sealing pads to a source of compressed air supply.

21. In a can testing machine having a receiving end and a discharge end, the combination of a rotary carrier having mounted V thereon a multiplicity of circumferentially arranged can clamping heads and air balancing tanks, one tank for each head, means for admitting compressed air, at a place adjacent the receivingv end of the machine, to each can and its associated balancing tank, means for holding the compressed air in the cans and associated balancing tanks for a predetermined length ci' time, a stationary selector, operated by two opposed pressures,

and located adjacent the discharge end of the machine, and means for exhausting the' air from each can and its associated balaiicing tank into said selector. 22. In a can testing machine havinga receiving end and a discharge end, the combination of a rotary carrier having mounted thereon a multiplicity of circuinfercntially arranged can clamping heads, each head arranged to hold a group of cans, air balancing tanks mounted on said carrier, one tank for each head, means for admitting compressed air, at a place adjacent the receiving end of the machine, to each can and its` associated balancing tank, means for holding the compressed air in the cans and associated balancing tanks for a predetermined length of time, stationary selectors located adjacent the discharge end of the machine, there being as many selectors as cans in the group held by any one can clamping head, and means for exhausting the air from each balancing tank and separately from the several cans associated with each tank into associated selectors.

23. In a can testing machine, the combinat-ion of a rotary carrier having a multiplicity of circumferentially arranged can clamping heads and balancing tanks thereon, one tank associated with each head, means for admitting fluid under pressure, at a predetermined place, to a can held by each head,

and to an associated balancing tank, means for holding the fluid in said cans and associated tanks for a predetermined length of time, and a stationary selector, having actuating means operated by two opposing pressures, and means located at a predetermined place for exhausting the fluid from each can and its associated balancing tank into said selector. I

24. In a can testing machine, the combination of a rotary carrier having a multiplicity of circumfcrentially arranged can clamping heads thereon, each head capable of holding several cans, balancing tanks, one for each head, means for admitting coinpressed air, at a predetermined place', to cans held by each can clamping head and to its associated balancing tank, means for holding the air in said cans and tanks for a predetermined length of time, and can selecting and separating mechanism including several pneumatically operated selectors and means adjacent the discharge end of the machine for establishing communication between the selectors and the balancing tanks and their associated cans, there being as many selectors as there are cans held by any one clamping head. l

25. In a can testing machine, a pneumatically operated selector comprising a pair ot opposed air gauge springs, air conduits connectedthereto and arranged to communicate respectively with a can to be tested and with an air balancing tank, a swinging actuating member, operatively connected to both of said air gauge springs and capable of being moved thereby from a normal inoperative position to an operative position, and

Vadjustment-.means for varying the normal position ofsaid actuating member.

26. In acan testing machine, a pneumatically operated selector comprising a pair of opposed air gauge springs, air conduits connected thereto and arranged to communicate respectively with al can to be tested and with an air balancing tank, a rock shaft operatively connected with said air gauge springs' and receiving motion therefrom, a swinging actuating member mounted on said rock shaft, and capable of being moved thereby from a normal inoperative position to an operative position, and adjustment means for varying the normal position of said actuating member on said rock shaft.

27. 'In a can testing machine a stationary selector having actuating means operated by two opposing pressures, a carrier lfor carrying cans, containing compressed air, past said selector, means carried by saidpcarrier, for containing compressed air Aof substantially the same pressure as in the cans, and means for exhaustin the pressure from the cans and compressedr air containing means into the selector. j

28. In a can testing machine, a carrier having can clamping heads mounted thereon for carrying cans containing compressed air, and having balancing tanks containing compressed air of substantiallyv the same pressure as that in the cans, a selector having means operated by two opposed pressures, said Vselector being separate and distinct from said means, and controlled means for exhausting the air from said cans and tanks into said selector.

CHARLES D. MCDONALD. 

